Low density parity check encoder, and low density parity check encoding method using the same

A low density parity check (LDPC) decoding method, comprising:

• receiving a signal corresponding to an LDPC codeword, the LDPC codeword generated by performing accumulation at parity bit addresses that are updated using a sequence corresponding to a parity check matrix (PCM);
• and
• decoding the received signal, the decoding corresponding to the parity check matrix,
• wherein the LDPC codeword comprises a systematic part corresponding to information bits, a first parity part corresponding to a dual diagonal matrix of the PCM, and a second parity part corresponding to an identity matrix of the PCM.